We're going to turn to rome and the latest on the pope's startling resignation. The first time in 600 years a pope has done this. Look at this photo. It's going viral madly monday. Of a bolt of lightning striking st. Peters, the same day the pope announced he will step down. Benedict is set for a new name, a new home and a new role. Dan harris is live in st. Peters square this morning with all of that. Dan, good morning to you. Reporter: Elizabeth, good morning to you. Here's how the local papers are playing this huge story. This one says, in italian, pope shock. And here's a headline, amen. As catholics all over the world absorb this truly stunning news, today, we're starting to get a sense of what may have provoked the pope to make this announcement now. This morning, the news agency says the pope had a top-secret operation to replace his pacemaker at this hospital in rome three months ago. The vatican won't confirm the news. But the paper says the operation went, quote, well. The pope's older brother held a news conference the day the decision was well thoughtout and nobody pushed his brother out. Meanwhile, benedict's surprise decision has provoked vatican intrigue, worthy of a dan brown novel. Jockeying and politicking has begun over who will be the 266th pope of this 2,000-year-old church, the largest religious body on earth. If I was a cardinal and I really wanted to be pope, could i actually campaign for myself? Well, I guess it would appear indiscreet. Reporter: It would not go over well? I don't think it would go over well. Reporter: While there are no clear favorites, bookmakers are laying odds. And here are three names you'll be hearing a lot. Cardinal peter turkson of ghana is listed as a 9-4 favorite. He would be the first black pope. The first we've heard of it before. Reporter: Canadian marc ouellet, a 5-2 favorite. And archbishop angelo scola of milan, who has a strong power base. Roughly 120 cardinals will gather under heavy security and beneath a cloak of secrecy for the conclave to choose a new pope inside the sistine chapel. Every time they vote, they burn the ballot. Black smoke means no pope yet. White smoke, a winner. It's not like voting for a president, where you're voting for the guy who will lower your taxes. Precisely. I want to vote as god wants. That's a very scary thing. Reporter: Scary, indeed. One more picture I want to show you this morning. This is the building where pope benedict will live once he officially steps down on FEBRUARY 28th, AT EXACTLY 8:00 P.M. This is a former monastery inside vatican city. For months, construction crews have been rehabbing this building. During that entire time, only a few top vatican officials actually knew this would ultimately become the pope's retirement home.

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